Research on High-Precision Acoustic Positioning Algorithm for Small-Scale Confined Underwater Space

In this paper, a underwater acoustic high-precision positioning system is investigated for the accurate positioning of the UUV in small confined space. The least squares Newton (LSN) algorithm based on Modified Chirp-z Transform (MCZT) with generalised quadratic correlation delay estimation is designed. The algorithm is modelled on an eight element cubic array. The MCZT algorithm produces the correlation function with more sharp peaks and higher peaks, resulting in more accurate delay estimates. The LSN algorithm performs a more accurate time-delay localization. Positioning simulations at different SNR and different locations are performed and experimental verification is conducted in the anechoic pool. Simulation results show that the LSN algorithm can achieve high accuracy positioning. Experimental results show that the UUV positioning error is controlled within 20mm, achieving high-precision positioning requirements.